Feline Oral Malignancies Study Guide

Overview and Clinical Importance

Oral malignancies account for approximately 10% of all feline tumors and represent the fourth most common site for neoplasia in cats. Unfortunately, 85-90% of oral tumors in cats are malignant, making early recognition and diagnosis critical. Squamous cell carcinoma (SCC) dominates this category, representing 60-80% of all feline oral tumors, followed by fibrosarcoma (10-20%) and other less common malignancies including melanoma, lymphoma, and osteosarcoma.

Feline oral squamous cell carcinoma is recognized as a naturally occurring model for human head and neck squamous cell carcinoma due to similarities in clinical presentation, biological behavior, and molecular markers. The prognosis for most feline oral malignancies remains poor, with median survival times ranging from 2-4 months despite aggressive treatment, emphasizing the importance of understanding these diseases for board examination purposes.

Epidemiology and Signalment

General Demographics

Major Types of Feline Oral Malignancies

Feline Oral Squamous Cell Carcinoma (FOSCC)

Pathophysiology

FOSCC arises from the squamous epithelium lining the oral cavity and is characterized by extremely aggressive local invasion with destruction of underlying bone. The tumor frequently invades the mandible or maxilla, causing osteolysis through production of parathyroid hormone-related protein (PTHrP) and other osteoclast-activating factors. While local invasion is severe, distant metastasis is relatively uncommon at diagnosis (less than 10-20%), though regional lymph node involvement occurs in 10-30% of cases.